A double murder over the weekend has shaken a tight-knit community in San Jose, California. The bodies of Shamima Rabbi, 57, and Golam Rabbi, 59, were found Sunday in their home. Both had been shot. Double murders are always news, but there’s more to this story–chilling details that have many in the community looking for a serial killer.

The police aren’t releasing many details, but told the local paper that the “incident was not a random act of violence and the suspect was someone familiar to the family.” But someone close to the investigation has leaked information that a note was found with the body that reads “Sorry my first kill was clumsy.”

As if that weren’t enough, the Rabbis were active members in the San Jose Islamic community. While authorities are not yet treating this as a blatantly anti-Islamic hate crime, the idea has not been ruled out. Instead, authorities are focused on the disturbing nature of the note–the playfully apologetic tone of a sadistic killer.

“Sorry my first kill was clumsy.” The implication here is that the couple were not the killer’s first victim. While the note could potentially refer to this murder, it more likely references another–perhaps a seemingly unconnected killing. And the satirical apology demonstrates a disconnect between the killer’s actions and his perception of the crime.

The police are still trying to locate members of the Rabbis family for questioning. One son, a minor, has not been located. Another, an adult, is also wanted for questioning, though he’s not a suspect. The Evergreen Islamic Center, where the Rabbis were active, have support on hand for members of the community who may need support.

If you know anything about the crime, call San Jose police Homicide Sgt. Pat Guire or Det. Ken Tran at 408-277-5283 or the Crime Stoppers Tip Line at 408-947-7867.